User:Rmal21/Draft

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Rmal21/Draft
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Coleoptera
Family:	Staphylinidae
Subfamily:	Staphylinoidea
Genus:	Creophilus
Species:	C. maxillosus
Binomial name
Creophilus maxillosus (Linnaeus, 1758)

Creophilus maxillosus belongs to the order Coleoptera and is most commonly reffered to as the hairy rove beetle. Rove beetles comprise a large family, having almost 2,900 species in North America. This species can be found in woods and wherever carrion is found, usually from the spring to autumn months. They are easily characterized by short elytra, which cover the first few abdominal segments and are black or dark brown in color. They have large, prominent eyes, and very sharp mandibles that close across eachother at the head which can inflict a painful stap if harrassed or handled carelessly. These active beetles fly swiftly or run rapidly over the ground with the tip of the abdomen raised like a scorpion's stinger. Although a few are known to be parasitic, most rove beetles and their larvae prey upon mites, other insects, and small worms.

Physical Characteristics and Life Cycle

Larvae of the hairy rove beetle run from 20 to 25 mm and are cylindrical and stout. The adult is a shiny black color and approximately 13-20 mm long. Golden setae are located on posterior angles of the head and slightly on the anterior angle of the pronotum. These setae can be found on the last few abdominal segments and on elytra. Similar to other Rove Beetles, the last few segments of the abdomen curve up like a scorpion’s stinger when running rapidly over ground. The hairy rove beetle has needle-like jaws that close across in front of head and large, prominent eyes. The antennae are thick, beaded, and composed of 11 segments.

The development of eggs is around 4 days, larvae 14 days, and pupae 16 days. The eggs are milky white colored, 2 to 3 mm long and hatch around 3 days with slight temperature dependence. The larval stage will last around 14 days. The pupae, which is around 11 mm wide lasts 13 days. The estimation of the total duration of Creophilus maxillosus lasts 37 days.

Habitat and Geography

Generally, C. maxillosus are found throughout the eastern U.S in the fall and spring, but can also be found in the summer. They are usually in wooded habitats such as forest leaf litter, decaying plant material (including fruit), and under dead tree bark (1). They can also be found in carrion, dung, under stones or rocks, and in fresh water areas in washed-up brown algae.

Defense Mechanisms

C. maxillosus has abdominal defensive glands used to secrete a toxin. These glands are located benearth the abdominal tergites. When threatened or disturbed, the beetle revolves its abdomen and touches abdominal tip to offender to wipe the glands. Ants (Formica exsectoides) are a common offender and have portrayed that this defense takes place. The ants are shown to be repelled by the four major components of secretion (isoamyl acetate, iridodial, E-8-oxocitronellyl acetate, and dihydroneptalactone). Dihydroneptalactone is the main principal ingredient of chemical defense.

Diet

This particular species is predacious in both the larvae and adult stages of life. The larvae and adults have long, curved mandibles which are used for chewing. They feed on carcasses (hours after death all the way up to the advanced stages of decomposition), as well as on maggots (fly larvae) that tend to be on dead animals.

Control

The hairy rove beetle is considered beneficial in the environment because it is a successful scavenger and predator. However, at times this beetle might infest houses. A study has shown that C. maxillosus adults like to lay eggs in fresh sand and not sand that is old or contaminated. Certain pesticides affect the adults and larvae of this beetle and can be used to control their numbers. Atroban a chemical pesticide composed of permethrin (0.05%) decreases the number of adults and larvae of the family Staphylinidae. Short term reductions of this family were caused by demethoate (0.05%). Both of these pesticides were tested moist spots on poultry dung.

Forensic Relevance

Creophilus maxillosus is one of the many forensically important insect species commonly encountered during crime scene investigations. This species can be used in investigative forensic entomology to aid in approximating the time of death of victims or the duration of carrion exposure, when found on carrion at crime scenes.

Both the larvae and adults of this predacious insect feed on the organic remains of carrion, as well as diptera larvae, and their presence on carrion is very closely related to the presence of diptera and diptera larvae. This predation is occasionally taken into consideration when forensic entomologists’ investigate carrion. The presence of C. maxillosus on carrion is sometimes associated with a marked reduction or absence of diptera larvae, which could be misleading and cause a misrepresentation of the overall entomofauna.

Forensic Case Studies

A study done by Szymon Matuszewski (Adam Mickiewicz University - Poznań, Poland) in central Europe explores insect succession on near identical swine carcasses set out in a pine-oak forest, hornbeam-oak forest, and an alder forest in western Poland. The team used a modified version of the stages of decomposition defined by Payne to base the finds, with each carcass sectioned into the head and trunk regions, to account for the differing rates of decomposition. The results show that C. maxillosus adults begin to appear during the ‘late-bloating’, ‘early-active’ phase and were present up to the earlier stages of the ‘remains’ phase. On average, they were first seen after about 6 days of decomposition (range of 5-7 days of decomposition ) and the last C. maxillosus adults were observed on average on day 25 of decomposition (range of 14-38 days of decomposition ). C. maxillosus larvae began to appear after an average of 17 days of decomposition (range of 13-25 days of decomposition) and were present until day 40 of decomposition (range 34-50 days of decomposition).